An electrical system includes a stack (3) of electrochemical cells (5), a power converter (9) electrically connected to the stack (3), a voltage comparator (7) for comparing the voltage at the terminals of at least one group of at least one electrochemical cell (5) of the stack (3) to a threshold voltage, and a control module (11) for controlling the converter (9). The control module (11) includes a generator (74) for generating a control instruction for controlling the converter (9) and a transmission member (76) for transmitting the control instruction to the converter (9). The voltage comparator (7) is suitable for transmitting a signal to the transmission member (76). The signal consists of a first instruction from an instruction for transmitting and an instruction for blocking the control instruction when the compared voltage is higher than the threshold voltage, and a second instruction from the instructions for transmitting and blocking the control instruction when the compared voltage is lower than or equal to the threshold voltage.

A method of operating a fuel cell system which includes a plurality of fuel cells and a plurality of auxiliary components located in at least one cabinet, includes monitoring, by a control unit, a parameter of the fuel cell system, determining whether the parameter has violated a threshold, and varying an auxiliary bus voltage provided to the plurality of auxiliary components connected to a common auxiliary bus by a first amount in response to determining that the parameter has violated the threshold.

An electrical power generating system for providing auxiliary or backup power to a load bus. The system may be used indoors, and generally includes a fuel cell unit comprising a first DC output, an electrical storage unit comprising a DC input coupled to the first DC output of the fuel cell, the electrical storage unit further comprising a second DC output. An inverter coupled to the second DC output receives power, the inverter comprising a first AC output. The system includes a contactor connected between the first AC output and an AC load bus. The AC load bus comprises an AC voltage, and a controller comprising inputs is adapted to sense a phase, a frequency, and a magnitude of the first AC output and the AC voltage and close the contactor when they substantially match.

Disclosed is a method of controlling an air supply system for a fuel cell. The air supply system includes a fuel cell stack, an air channel to supply air to an inlet of the fuel cell stack, a gas adsorption unit disposed on the air channel and configured to adsorb oxygen contained in air introduced into the air channel. In particular, the method includes: determining whether a power generation operation of the fuel cell stack is resumed; when the power generation operation of the fuel cell stack is resumed, controlling a voltage source to apply a voltage to the gas adsorption unit; and supplying air to the fuel cell stack through the air channel in a state in which the voltage is applied to the gas adsorption unit.

On a start of a fuel cell system, (i) when the temperature of a high-voltage secondary battery obtained from a temperature sensor is higher than a predetermined reference value, a controller of the fuel cell system is configured to set an output voltage on a step-down side of a DC-DC converter to a higher voltage than a voltage of a low-voltage secondary battery and subsequently start an FC auxiliary machine using electric power from the high-voltage secondary battery. (ii) When the temperature of the high-voltage secondary battery obtained from the temperature sensor is equal to or lower than the predetermined reference value, on the other hand, the controller of the fuel cell system is configured to set the output voltage on the step-down side of the DC-DC converter to a lower voltage than the voltage of the low-voltage secondary battery and subsequently start the FC auxiliary machine using the electric power from the high-voltage secondary battery.

A fuel cell system includes a fuel cell, an electrical storage device, a fuel-cell-side converter, an electrical-storage-device-side converter, and a controller. The fuel cell is to output fuel cell voltage. The fuel-cell-side converter is configured to apply the fuel cell voltage to a load in a direct connection state or configured to apply a stepped-up fuel cell voltage to the load. The electrical-storage-device-side converter is configured to apply a stepped-up electrical storage device voltage to the load. The controller is configured to control duty of the electrical-storage-device-side converter so that the fuel cell voltage changes smoothly in a case where a state in which the fuel cell voltage is controlled by the fuel-cell-side converter is switched to a state in which the fuel-cell-side converter is set to the direct connection state and the fuel cell voltage is controlled by the electrical-storage-device-side converter.

A fuel battery system includes a fuel battery, an electric storage, a voltage adjuster, a pump, an abnormity detector, and circuitry. The fuel battery generates electricity using fuel gas and oxidant gas. The voltage adjuster is connected to at least one of the fuel battery and the electric storage. The voltage adjuster is configured to adjust voltage output from the fuel battery or the electric storage to output the adjusted voltage to a load. The pump supplies the oxidant gas to the fuel battery using electric power output from at least one of the fuel battery and the electric storage. The voltage adjuster is connected between the fuel battery and the pump. The abnormity detector detects abnormity in the voltage adjuster. The circuitry is configured to restrict the electric power supplied to the pump in a case where the abnormity detector detects the abnormity in the voltage adjuster.

An air supply system for a fuel cell includes: a fuel cell stack in which multiple unit cells are stacked and that generates electricity through chemical reactions, an air channel to supply incoming air containing oxygen to the fuel cell stack and to transfer air discharged from the fuel cell stack to the outside of the air supply system, and a gas adsorption unit that is disposed on the air channel, positioned near an outlet of the fuel cell stack, and adsorbs oxygen contained in the air introduced into the air channel.

An electrical power generating system for providing auxiliary or backup power to a load bus. The system may be used indoors, and generally includes a fuel cell unit comprising a first DC output, an electrical storage unit comprising a DC input coupled to the first DC output of the fuel cell, the electrical storage unit further comprising a second DC output. An inverter coupled to the second DC output receives power, the inverter comprising a first AC output. The system includes a contactor connected between the first AC output and an AC load bus. The AC load bus comprises an AC voltage, and a controller comprising inputs is adapted to sense a phase, a frequency, and a magnitude of the first AC output and the AC voltage and close the contactor when they substantially match.

The power supply device is configured on an aircraft and includes a secondary battery, a transformer, a fuel cell and a bypass switch. The transformer is electrically connected between the secondary battery and the aircraft. The fuel cell is suitable for providing a first output current to the aircraft. The bypass switch is connected in parallel with the transformer. The transformer has a first output voltage set value. When a first output terminal voltage of the fuel cell is lower than the first output voltage set value and the bypass switch is in a non-conducting state, a second output current of the secondary battery is provided to the aircraft via the transformer. When the first output terminal voltage is lower than the first output voltage set value and the bypass switch is in a conducting state, the second output current is provided to the aircraft via the bypass switch.